Kevin McCarthy, who was ousted as the Republican speaker of the US House of Representatives in October, has announced that he will resign from Congress at the end of the year.
The departure of the 58-year-old congressman from California will leave Republicans with a slim 220-213 majority in the chamber.
Mr McCarthy's announcement comes days after George Santos, a scandal-plagued Republican representative from New York, was expelled from the House, just the sixth member to be thrown out since Congress began deliberating in 1789.
Two months ago, Mr McCarthy become the first speaker to be ousted in the House's 234-year history.
He was removed in a rebellion by far-right members of his Republican Party furious at his cooperation with Democrats.
The former entrepreneur sparked fury among conservatives when he passed a bipartisan stopgap funding measure backed by the White House to avert a government shutdown.
In a column in The Wall Street Journal announcing his resignation, Mr McCarthy, who was elected to Congress in 2006 and whose latest two-year term had been scheduled to end in January 2025, said he would remain involved in Republican politics.
"I know my work is only getting started," he said. "I will continue to recruit our country's best and brightest to run for elected office.
"The Republican Party is expanding every day, and I am committed to lending my experience to support the next generation of leaders."
Ronna McDaniel, the chairwoman of the Republican National Committee, issued a statement thanking Mr McCarthy for his service, calling him "a dedicated public servant and a happy warrior."
"We wouldn't have a Republican House majority without him," Ms McDaniel said. "While I'm sad to see him go, I wish him all the best in his next chapter."
Special elections will be held in California and New York to replace McCarthy and Santos in the 435-seat House of Representatives.
Stormy relations
His tenure as speaker was marked by stormy relations with Republican hardliners, who forced him to endure 15 humiliating floor votes before receiving the gavel last January, and then voted him out on 3 October after he backed a bipartisan spending measure that averted a government shutdown.
"No matter the odds, or personal cost, we did the right thing. That may seem out of fashion in Washington these days, but delivering results for the American people is still celebrated across the country," McCarthy wrote.
He was replaced by Speaker Mike Johnson, a relative newcomer to the leadership, after weeks of Republican infighting in which three more seasoned candidates were nominated and then rejected.
Mr McCarthy ran afoul of hardliners when he publicly said that then-President Donald Trump bore responsibility for the deadly 6 January 2021, attack on the US Capitol, days after the violence, though he later repeatedly voiced allegiance to the former president.
Mr McCarthy also drew their ire earlier this year by striking a deal with Democratic President Joe Biden that averted a default on US debt and set a $1.59 trillion spending limit for fiscal 2024.
Hardliners shuttered the House floor for days over the spending agreement but have since said they would accept it.
Mr McCarthy was the first US House speaker to be ejected from the chair. But he will become the third Republican speaker, after John Boehner and Ryan, to leave Congress following repeated clashes with the Republican hard right.
He launched an impeachment inquiry into Mr Biden, focused on Biden's son Hunter Biden's business dealings, which Democrats have denounced as politically motivated and unsubstantiated by evidence.
Mr McCarthy won reelection in 2022 by a 35-point margin, and his California district is not seen as competitive by the three main nonpartisan election forecasters.
